Fuel feeding valve



Jan:'5,1932.-- 7 HROHWER 1,840,256

I FUEL FEEDING VALVE Filed Jan. 24, 1930 B v x MQ i.

- tion of the needle seat & curately normally to the needle.

come these drawbacks which Patented Jan. 5, 1932 UNITED STATES PATENT OFFICE HEINRICH ROHWER, 0F KIEL, GERMANY, ASSIGNOR TO FRIED. KRUPP GERMAINIA- WEIRFT AKTIENGESELLSCHAFT, 0F KIEL-GAARDEN, PRUSSIA, GER-MANY FUEL FEEDING VALVE Application filed January 24, 1930, Serial No. 423,234, and'in Germany February 7, 1929.

Theinvention relates to fuel-feeding valves of the needle type for internal combustion engines, more particularly Diesel engines.

In designing fuel-feeding valves of this type it is well-known to provide a special needle seat body having a shape like a plate and the conical shell surface of which is pressed by a screw cap with the necessary tightening pressure on to a corresponding conical face of a needle guiding sleeve.

.Upon the screw cap being unscrewed which is necessary for instance for cleaning the spray nozzle, this known needle seat body takes part in the unscrewing rotation and is E thus disconnected from the needle sleeve. Therefore, in re-assembling the needle seat body does not longer assume its original position relatively to the needle and needle sleeve, whereby leakage of the valve may be caused.

Furthermore, in employing the known needle seat body it is a condition for a tight closure of the valve that the internal abutting face of the screw cap be always directed ac- Already quite a deviation from this position will cause the needle seat body to not assume its position determined by the conical tightening faces but to be tightened obliquely. The reason therefor is that owing to the plate shape of the needle seat body the narrow conical faces do not form a reliable straight guide but act like a ball joint, and that the position of the needle seat body always depends upon the position of the internal face of the screw cap.

Now the object of the invention is to overobject is achieved by the fact that according to the invention the seat for the fuel needle consists of a separate hardened tubular member which, conically fits with adhesive friction in an extension of the needle sleeve and is pressed with the necessary tighteningpressure into this sleeve by means of a nozzle member that forms an abutment therefor and includes the spraying hole, so that an accuratecentral posi- 1S obtained.

In order that the invention can be more readily understood, an embodiment of the same is illustrated by way of example in the accompanying drawing which shows the lower portion of a fuel-feeding needle valve in longitudinal section. e

A denotes the lower portion of the valve casing, B the needle sleeve fitting therein, and C denotes the fuel needle. According to the invention the seat for the needle 0 is formed by an inserted tubular member D made of a suitable hardened material and conically fitting in the extension of sleeve B with adhesive friction. position from outside by the nozzle member and pressed into sleeve B with the required tightening pressure by tightening home member E.

Fuel is supplied under high pressure through passage F and enters the annular chamber G above the needle seat.

When the needle G is lifted the fuel enters the combustion chamber of the cylinder through the inserted member D and nozzle member E in the shape of separate jets.

When compared with known fuel needle valves in which needle sleeve and needle seat are made in one piece the described design affords the advantage that the seat can be hardened very satisfactorily. Furthermore, it is possible when turning out the annular chamber G, to introduce the turning tool through the extension of sleeve B so that a much shorter tool can be used whereby the turning work becomes more accurate. In comparison, further, with needle valves in which the needle seat is provided in the nozzle plate, the present arrangement affords the advantage of the seat being capable of being centered more accurately owing to the tapered shape of the inserted member D.

l/Vhat I claim and desire to secure by Letters Patent, is

1. A fuel valve comprising a casing, a valve needle therein, a guiding sleeve for said nee- The member D is held in 7 dle in said casing, an extension on said sleeve extending beyond the point of said needle, a

seat body for said needle firmly fixed in said 1 extension by a pressed fit and projecting beyond it and adapted to remain fixed therein when the valve is disassembled, and a nozzle member adapted to be screwed on to said cas 2 emmaing and to tighten thereby said seat body in V said extension.

i 2. A fuel valve comprising a casing, a valve needle therein, a guiding sleeve for said nee- 5 dle in said casing, an extension on said sleeve extending beyond the point ofsaid needle, a tubular seat body for said needle with a slight taper on itsexterior firmly fixed in said extension by a pressed fit and projecting beyond it, and adapted to remain fixed therein when the valve is disassembled, and a nozzle member adapted to be screwed on to said casing and to tighten thereby said seat body in said extension.

3. A fuel valve comprising a casing, a valve needle therein, a guiding sleeve for said needle in said casing, an extension on said sleeve extending beyond the point of said needle, a cylindrical seat body for said needle firmly fixed'in said extension by a pressed fit and adapted to remain fixed therein when the valve is disassembled, and a nozzle member adapted to be screwed .onto said casing, abutting said seat body at the end opposite the needle seat;

The foregoing specification signed at Ham burg, Germany, this 9th day of January.

1930. i 3 HEINRICH RQHWER o I 

